Locked paper box



Oct. 6, 1953 MCREARY 2,654,526

LOCKED PAPER BOX Filed Aug. 18, 1952 2 Sheets-Sheet l l I27 27 I INVENTOR.

RONALD MC REARY ATTORNEY R. M REARY LOCKED PAPER BOX Oct. 6, 1953 2 Sheets-Sheet 2 Filed Aug. 18, 1952 INVENTOR. RONALD MC REARY BY ATTORNEY Patented Oct. 6, 1953 OFFICE LOCKED PAPER BOX Ronald. McReary, Portland, reg., assignor to Harry M. Mathers, Portland, Greg Application August 18, 1952, Serial No. 305,012 Claims. (01. 229-33)- The present invention, like that described in my co-pending application for patent, Serial No. 141,026, entitled Interlocking Sections for Paper Boxes, and filed under date of January 28, 1950,. relates to boxes of the knock-down type, made from relatively thin, semi-flexible paper board, or similar material, and this application is a continuation-in-part of my co-pending application Serial No. 141,026, now Patent No. 2,610,782.

An object of this invention is to provide novel and improved means for enabling the two sections of the box, namely the cover section and the bottom section, to be locked to each other in closed position when the box is completely closed.

A related object of the invention is to provide a paper box construction in which the improved locking means will be integral with the box walls and formed with the initial stamping out of the box blank from the paper board or material for the box.

A further object of the invention is to provide an improved paper box in which the overlapping walls of the cover and bottom sections can be strongly interlocked when the box is closed, even though the box is made from relatively thin paper board, and which interlocking will hold the overlapped walls firmly adjacent and parallel to each other where the interlocking occurs even though the outside wall is distorted or caused to bulge.

An additional object of the invention is to provide a paper board box which can be locked and unlocked a number of times without impairing the interlocking means.

These objects I attain by constructing my improved box and box locking means as explained in the following specification with reference to the accompanying drawings forming part thereof. In the drawings:

Fig. 1 is a perspective view of a box having the customary bottom and cover sections, made from a single blank, and embodying my improved locking means, this figure showing the box partly open and with one end of the front wall of the cover section broken away to show the adjacent end of the side wall of the cover;

Fig. 2 is a plan view of the entire blank from which the box of Fig. 1 is made;

Fig. 3 is a fragmentary perspective view of a front corner of the box of Fig. l but with the cover section in closed but unlocked position;

Fig. 4 is a fragmentary side elevation of the closed box showing the same corner but with the front wall of the cover and the end flap of thewall bent forwardly for the sake of clarity;

Fig. 5 is a perspective view of the box corner of Fig. 3 illustrating the manner in. which the locking of the cover is performed at that corner of the closed box;

Fig. 6 is a corresponding perspective view showing the same corner fully locked; and

Figs. 7 and 8 are fragmentary plan sections taken on the planes indicated by the lines 5-? and il-B. respectively in Fig. 6 but drawn on an enlarged scale.

The box illustrated in Fig. 1 is formed from. thesingle integral blank shown in Fig. 2, the broken lines of Fig. 2 indicating the crease lines on which the folding occurs when the box is set up. The bottom section It includes a front wall l4 and side walls [2 and [3. A top or cover section ii similarly includes a front wall [8 and side walls It and H. The back wall i5 is common to bottom and cover sections and constitutes the hinge connection between. themw In the form of box. illustrated the front and side walls of the top or cover section are intended to extend down over the outside of the corresponding front and side walls of the bottom. section when the box is closed.

The front wall ill of the cover section has a pair 01 identical flaps 29 and 20' (Fig. 2) extending from each. end of the wall, and when the box is set up these flaps are folded on the broken lines is and I9 respectively. When the box is completely closed and locked these flaps are intended to overlie portions of the side walls H and i6 respectively, as will presently be apparent. Each of these flaps Z0 and 2c terminates in a tongue-like end 2 l. A curved slit in each of these flaps 20 and 2|! forms a second inner tongue 22. The inner tongues 22 extend inwardly on their respective flaps or towards the fold lines 59 and I9 at the corresponding corners of the front wall, and consequently each inner tongue 22 extends in an opposite direction from that in which the end tongue 2! of the particular flap extends. Each tongue 22 is adapted to be bent inwardly slightly on the crease line 23'.

Each of the side walls I! and it of the cover section It has an identical cut-out aperture 24 located near the end adjacent the front wall it. Each cut out aperture 24 is preferably trape zoidal in shape and has two opposite edges 26 and 25 (Fig. 2) which are both parallel to the front edge of the side wall in which the cut-out aperture is located. The distance of the edge 26 from the adjacent front edge of the wall is the same as the distance between the crease line 23 of the tongue 22 and the fold line as of the adjacent wall end flap, the edge 26 being preferably approximately the same length as the crease line 23, and when the box is closed and looked as later described, the crease line 23 and aperture edge 23 should be substantially in registration. The distance between the two opposite edges 25 and 2B of the aperture 24 is considerably less than the distance between the crease line 23 and the end of the tongue 2|.

On each of the side walls l2 and I3 of the bottom section It the slot 21 is cut of approximately the same length as the edge 25 of the aperture 2d and is so positioned in the bottom side wall that it will be in registration with the edge 26 of the aperture of the corresponding side wall of the cover when the box is completely closed. Preferably, though not necessarily, a branch slot 21 is added to the slot 21 so as to .make a combined T-shaped slot as illustrated in Figs, 1 and 2.

When the cover section I! of the box is closed down over the bottom section [8, with the front and side walls of the cover section overlying the front and side walls respectively of the bottom section, the interlocking of the two sections is obtained in the following manner:

The flaps 2t and at the ends of the front wall l8, will initially be in some such position as illustrated by the flap 20 in Fig. 3, when the cover is first closed. The tongue-like end 2! of one of these flaps, for example of the flap 20, is inserted in the adjacent aperture 24 of the near side outer wall (thus the wall 11) so'that the tongue end 2! will pass under the far edge of the aperture 24 and be in position to be slid in between the outer and inner side walls (thus between the walls I? and I3). At the same time the inner tongue 22 of this flap is pressed inwardly over the edge 26 of the aperture 24 and into the underlying slot 21 of the inner side wall l3 (of the bottom section). The flap 2'] will now momentarily be in the position illustrated in Fig. 5. Then, by pressing the bulging portion of the flap 20 against the side of the box, the flap will be pushed into the final interlocking position illustrated in Fig. 6 (and also illustrated in Figs. 7 and 8). The inter-,- locking of the top and bottom sections on the other side walls of the box is accomplished similarly with the other flap 20.

To unlock the box each of the flaps 20 and 20 in turn is pulled outwardly at the center, first into the position illustrated in Fig. 5 and then further into the entire unlocked position illustrated in Fig. 3.

It will be apparent from Figs. 4, 6, 7 and 8 that when the inner tongue 22 is inserted past the edge 25 of the aperture 24 into the underlying slot 21 and the flap 2t is held in place against the outer side Wall IT, by the insertion of the tongue and end 2| under the edge 25 and outer side wall, the front end portions of the outer and inner walls H and it will be held firmly adjacent and parallel to each other,.in addition to the fact that the outer wall will be held against any upward movement with respect to the inner wall, as long as the flap 2e remains in place, and the flap 20, in the position shown in Figs. 6, 7 and 8, will remain in place until it is manually pulled outwardly for the unlocking of the box. Even if the outer side wall E? is caused to bulge or is pulled outwardly away from the inner wall !3 along the center portion of the bottom of the wall I1, the front edge 26 of the aperture 24 in the wall 17 will still be held in place adjacent the underlying portion of the inner wall i3 by the tongue 22 in the locking slot 27, and until the fiap 20 is pulled outwardly to withdraw the tongue 22 from the locking slot 21.

Such an outward bulging of or pull on the outer wall I! away from the inner wall I3 could not result in pulling the flap 22 out far enough to unloci; or disengage the tongue 22 from the slot 2'! unless tearing or mutilation of the box occurred. Thus the locking of the front end of the two walls in adjacent position at the edges 26 and slots 21 by the tongues 22 will be maintained under all normal conditions in spite of any bulging of one or both of the interlocked pairs of side walls. This is an important feature in my improved locking construction and is particularly important when the box is made of quite thin flexible paper board,

There is an advantage in providing a T-shaped slot 21, 21' in place of a single straight slot 21. The branch slot 2'! facilitates the inserting of the tongue 22 through the main slot 21 because the two corner sections formed by the junction of the branch slot 2'? with the main slot 21' will flex inwardly slightly as the tongue 22 is inserted in the main slot, thus temporarily enlarging the main slot throughout most of its extent and also permitting a very slight deforming of the inner wall to accommodate the tongue in locking position while maintaining some pressure against the inner face of the tongue. However, my invention can be employed satisfactorily with a single straight slot instead of the preferred form or T- shaped slot.

There is also a considerable advantage-in providing an aperture 2d, having the opposite edges 25 and 25, instead of merely having two parallel slots in the outer wall at the same location as the respective aperture edges 25 and 25. The aperture enables the end tongue 21 to be inserted easily and quickly into place between the two adjacent side walls, and also by exposing the T- shaped slot 2?, 2?, (when the T-shaped slot is provided) facilitates the inserting of the tongue 22 into locking position, and simplifies somewhat the stamping out of the original blank.

While I have illustrated and described my locked paper box with the flaps 2t and 25' on the ends of the outer front wall and with the apertures 24, and underlying slots 21 in the adjacent end portions of the respective pairs of side walls, it would of course be possible to have the flaps 2t, 21'? formed on the front ends of the outer side walls and the apertures 2d and lots on the ends of the outer and inner front walls, and similarly one flap 2-2 could be formed on the front end of one outer side wall and the other fiap 2 formed on the further end of the outer front Wall with the aperture and slot for the first fiap then being located in the outer and inner front walls and the aperture and slot for the second fiap being located in the second pair of side walls. also be employed in a box in which the bottom and cover sections are made from entirely separate blanks, in which case there would be tongued flaps at all four corners of the cover section, instead of at only two corners, and four corresponding apertures would be provided in the cover section walls and four registering locking slots in the underlying walls of the bottom sections.

1 claim: I

1. In a box construction of the character de scribed, a pair of companion sections, each section having front and side walls and the walls of one section adapted to overlie the corresponding walls of the other section respectively when said box is closed, a flap extending longitudilVIy i vention obviously could nall y" from a wall or said first mentioned section at a corner of said first mentioned section, said flap terminating in a tongue, at second tongue formed in said flap spaced longitudinally inward-1y from said end tongue and extending a direction opposite to that of said end tongue, an aperture cut out near the end of the wall of said first mentioned section adjacent the wallfrom which said flap extends, an engaging slot: for said second tongue of said flap located in the wall of said other section underlying said aperture when said box is closed, said aperture having an edge near the adjacent corner of said box registering with said slot when said box is closed and an opposite edge spaced further from the respective corner of said box and so located that the end tongue of said flap can be inserted under said opposite edge when the second tongue of the flap is inserted in said slot, whereby, when the second tongue of said flap is inserted in its slot and the end tongue of said flap inserted under said opposite edge of said aperture, said second tongue will lock the corresponding wall of said box sections together at said first mentioned edge of said aperture.

2. In a box construction having a bottom section and a cover section, each section having front and side walls and the walls of said cover section adapted to overlie the corresponding walls of said bottom section respectively when said box is closed, a plurality of flaps extending longitudinally from the walls of said cover section and located at successive corners of said cover section, each of said flaps terminating in a tongue, a second tongue formed in each of said flaps spaced longitudinally inwardly from said end tongue and extending in a direction opposite to that of said end tongue, a trapezoidal-shaped aperture cut out near the end of each of the walls of said cover section adjacent the walls from which said flaps extend respectively, engaging the slots for said second tongues of said flaps located in the walls of said bottom section underlying said apertures respectively when said box is closed, each aperture having an edge near the adjacent corner of said box registering with the respective slot when said box is closed and an opposite edge parallel to said registering edge and spaced further from the respective corner of said box and so located that the end tongue of the respective flap can be inserted under said opposite edge when the second tongue of the flap is inserted in its slot, whereby, when the second tongue of each of said flaps is inserted in its slot and the end tongue of each of said flaps is inserted under the opposite edge of the correspond ing aperture, said second tongues will lock the corresponding walls of said box sections together at said first mentioned edges of said apertures.

3. In a box construction, an inner section and an outer cover section, each section having front and side walls and the walls of said outer cover section adapted to overlie the corresponding walls of said inner section respectively when said box is closed, a flap extending longitudinally from each end of the front wall of said cover section, each of said flaps terminating in a tongue, a second tongue formed in each of said flaps spaced longitudinally inwardly from said end tongue and extending in a direction opposite to that of said end tongue, apertures cut out near the ends of the side walls of said outer cover section adjacent the front wall of said cover section, engaging slots for said second tongues of said flaps located in the walls of said inner section underlying said apertures respectively said box is closed, each aperture having an edge near the adjacent corner of said box registering with the respectiveslot when: said box is closed and anopposite edge spaced further from the respective corner of said box and so located that the end tongue of the respective flap can be inserted under said opposite edge when the second tongue" of the flap is inserted its slot, whereby, when the second tongue of each of said flaps is inserted in its slot and the end tongue of each of said flaps is inserted under the opposite edge of the corresponding aperture, said second tongues will lock the corresponding walls of said box sections together at said first mentioned edges of said apertures.

4. A box construction including a bottom section and. a cover section, each section having front and side walls and the walls of said cover section adapted to overlie the corresponding walls of said bottom section respectively when said box is closed, a pair of flaps extending longitudinally from the walls of said cover section and located at successive corners of said cover section, each of said flaps terminating in a tongue, a second tongue formed ineach of said flaps spaced longitudinally inwardly from said end tongue and extending in a direction opposite to that of said end tongue, identical apertures cut out near the ends of the walls of said cover section adjacent the walls from which said flaps extend respectively, engaging T-shaped slots for said second tongues of said flaps located in the walls of said bottom section underlying said apertures respectively when said box is closed, each aperture having an edge near the adjacent corner of said box registering with the main portion of the respective slot when said box is closed and an opposite edge parallel to said registering edge and spaced further from the respective corner of said box and so located that the end tongue of the respective flap can be inserted under said opposite edge when the second tongue of the flap is inserted in its slot, whereby, when the second tongue of each of said flaps is inserted in its slot and the end tongue of each of said flaps is inserted under the opposite edge of the corresponding aperture, said second tongues will lock the corresponding walls of said box sections together at said first mentioned edges of said apertures.

5. A box construction of the character described comprising a bottom section and a cover section integral with said bottom section, each section having front and side walls and the walls of said cover section adapted to overlie the corresponding walls of said bottom section respectively when said box is closed, a pair of flaps extending longitudinally from the walls of said cover section and located at successive corners of said cover section, each of said flaps terminating in a tongue, a second tongue formed in each of said flaps spaced longitudinally inwardly from said end tongue and extending in a direction opposite to that of said end tongue, identical trapezoidal-shaped apertures cut out near the ends of the walls of said cover section adjacent the Walls from which said flaps extend respectively, engaging T-shaped slots for said second tongues of said flaps located in the walls of said bottom section underlying said apertures respectively when said box is closed, each aperture having an edge near the adjacent corner of said box registering with the main portion of the respective slot when said box is closed and an opposite edge parallel to said registering edge and spaced further from the respective corner of said box and so located that the end tongue of the respective flap can be inserted under said opposite edge when the second tongue of the flap is inserted in its slot, whereby, when the second tongue of each of said flaps is inserted in its slot and the end tongue of each of said flaps is inserted under the opposite edge of the corresponding aperture, said second tongues will lock the corresponding walls of said box sections together at said first mentioned edges of said apertures.

RONALD McREARY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Bisler Aug. 19, 1884 Morrison July 28, 1914 Bachmann Apr. 22, 1930 Poe Apr. 13, 1943 McReary Sept. 16, 1952 

